If you do a Google search (or one here) you will find it - just search on "ferry Dominican republic to Puerto Rico". It is not cheap -like US$450 a couple overnight round trip. I think flying on AA might even be less money.
Mayag?ez-Dominican Republic (Nov. 15 -2005)
MS Caribbean Express Ferry $173-$401 (tax included) per person, round trip 12 hours one-way.
MAYAGUEZ 787-832-1750
METRO 787-7252643 / 2646 / 2654
DOMINICAN REPUBLIC 809-688-4400
Cars, Vans and others $112 - $212
Mayag?ez to Dominican Republic
Monday, Wednesday and Friday
Departure: 8 p.m.
Arrival:8 a.m. the next day
Dominican Republic to Mayag?ez
Sunday, Tuesday and Thursday
Departure:8 p.m.
Arrival:8 a.m. the next day
